Arc welding device



June 16, 1942. E, J. GORN 2,286,212

ARC WELDING DEVICE Filed March 15, 1941 SOU CE OF HYDROGEN INVENTOR,

Patented June 16, 1942 ARC WELDING DEVICE Elmer J. Gorn, Brookline,Mass, assignor to Raytheon Manufacturing Company, Newton, Mass., acorporation of Delaware Application March 15, 1941, Serial No. 383,598

8 Claims.

This invention relates to an arc welding device, particularly as appliedto the invention as described and claimed in the copendingapplication'of Laurence K. Marshall and John W. Dawson, on Are weldingsystem and method, Serial No. 360,796, filed October 11, 1940. In saidapplication there is described and claimed a. system in which an arcis'dispersed by. means of magnetic fields over relatively extended areasof two members to be welded, whereby said surfaces In an arrangement ofthis kind the conditions I at one polarity of the are are often moresuitable for optimum welding conditions than at the opposite polarity.

An object of this invention is to cause the same are polarity 'to existat each of the surfaces to be welded in order that the conditions ateach welding surface be more nearly alike as well as to select the moreadvantageous polarity.

A' further object of this invention is to produce a separate are at eachwelding surface so that the conditions at said surface may be adaptedfor optimum operation.

A still further object is to utilize a simple refractory electrode fromwhich each of"the dis persible arcs are maintained to the two surfacesto be welded.

The foregoing and other objects of this invention will be bestunderstood from the following description 01 an exemplification thereof,refa suitable refractory electrode 3 is located. This electrode may bemade of refractory carbon or some other suitable refractory conductingmaterial. Surrounding the pipes I -and-f2-respectively are two magneticshells l and 5. These magnetic shells are provided with aligned openingsthrough which the pipes I and 2 are inserted. The edges of the openingsin the shell 4 constitute pole pieces 8 and 9 while the edges of theopenings in the shell 5 constitute pole pieces III and II. In order toenergize the pole pieces, annular coils 6 and 1 are placed respecsourceof direct current, any other suitable type of current supply may bechosen. The energization of the coils 8 and I create radial fields atthe .pole pieces 8 and I0, respectively, which produce a transversecomponent of magnetic field in each of the arc gaps existing between thefaces of the electrode 3 and the adjacent ends of the pipes I and 2,respectively.

The electrode 3 is adapted to be moved selectively into positionadjacent the ends of the pipes I and 2 for the purpose of establishingan arc to each of said pipes and out of said position so that the pipesmay be moved into welding engagement with each other. For this purposethe electrode 3 is mounted on a conducting arm I3 which in turn iscarried by a rotatable shaft II. The axis of rotation of the shaft I4 issubstantially'at right angles to the plane of the end surfaces of thepipes I and 2 to be welded,

so that upon rotation of said shaft, the electrode 3 is readily movedout of its arc-maintaining position. Any suitable actuating means areprovided for the shaft I4. such that when the surfaces to be welded aresufficiently heated, the electrode 3 is rapidly moved out of itsarc-maintaining position.

The pipe I is supported by a clamping ring I5 mounted upon base membersIS. The base members I6 are adapted to be moved in either directionalong the axis of the pipe I. Likewise the pipe 2 is held in position bymeans of a clamping ring I! mounted upon base members I8. Base membersI8 likewise are adapted to be moved in either direction along the axisof the pipe 2. The motion of the base members I6 and I8 may beautomatically coordinated with that of the shaft II so as to perform thevarious operations at the desired times and in the desired sequence.

In order to establish and maintain an arc to the ends of the pipes I and2, a source of arc current I9 is provided. This source may supply tohave the source I 9 supply direct current. One

terminal 20 01' the source I9 is connected directly t0 the conductingarm I3 and thus to the refrac- Preferably this means is pedance 22 tothe pipe I, extends through a current-limiting and controlnon-oxidizingatmosphere.

.and 2.

tory electrode 3. This terminal may. for example, be the negativeterminal of the source. The other terminal 2i of said sourceis providedwith two connections, one of which extends through a current-limitingand controlling imthe other of which to the pipe 2. Theimpediing'impedance 23 v be either resistances or inances 22 and 23 mayductances.

In some instances it may be desired to carry out the heating of thewelding surfaces in a For this purpose a non-oxidizing gas, such ashydrogen, may be supplied irom source 24. This source 24 may beelectrode adjacent the end walls of said members and separated from eachof said end walls maintaining said arcs while said electrode and wallsare held separated, means for moving each of said arcs rapidly along andthroughout the peripheral extent of the end walls to heat the end wallsrapidly throughout their peripheral extent,

connected through a pipe 26 which extends through a gas-tight plug 28 inthe lower end of the pipe 2, and supplies gas to the interior of saidpipe 2. The upper end of thepipe I may likewise be closed by a gas-tightplug 21. Under these conditions the hydrogen will flow into the pipe 2and out through the annular gaps provided between the electrode 3 andthe adjacent ends of the pipes I and 2. In. order that the gas may flowfreely to both of these gaps,

the electrode 3 is preferably made in annular form so as to provide anopennig in the center thereof.

Whenthe sources I! and II are energized, an arc is struck between theelectrode I and the adiacent ends of the pipes I and I by any suitablemeans. One way of accomplishing the initiation of the arcs is tomomentarily move the pipes I and 2 into engagement with the electrode 3.Once thearcs are established in the annular arc gaps. they will besubjected to the radial component of the magnetic field, and each arctherefore will spin rapidly around the ends of the pipes I and 2,causing the dispersion and uniform in said Marshall and Dawsonapplication. When I the end surfaces of the pipes I and 2 have beenraised to the proper welding temperature, the rot atable shaft llisactuated,rapid1y moving the electrode 3 out of position between thepipes I 'I'hereupon the base members It and "are moved toward eachother, bringing the ends of the pipes I and 2 into welding engagementwith-each other,-'thus producing the desired union of these twopipemembers.

In the arrangement as described above,.it will be seen that each-surfaceto be welded is subjected to an arc of the same polarity. Therefore theconditions at these two welding surfaces can be maintained to secureoptimum welding conditions. In some cases it may be desirable to createdifferent conditions at the two surfaces to be welded. For example, insome cases the size of the material of the two pipes may be different.The present arrangement permits an independent control of the weldingconditions at each of the surfaces as, for example, by properlyselecting the size and nature. of the current-limiting and controllingimpedances' 22 and 23.

Of-course it is to be understood that this invention is not limited tothe particular details as described above as many equivalents willsuggest themselves to those skilled in the art. I It is accordinglydesired that the appended claims be 3 Jbination, an electrode, means forholding said and means for applying pressure to the heated end walls tocause the heated end walls to become welded to each other.

2. A system for operating on two members each having faces connectedalong the thicknessg-"dimansions of themembers by an end wall to heatprocess the members along and throughout a predetermined extended lengthof the end walls, the system having, in combination, an electrode,meansfor holding said electrode adjacent said end walls butnon-contacting throughout said predetermined extended length, means forstriking an are between said electrode and each of said adiacentlydisposed end walls with the terminalsof the arcs engaging the electrodeand the,

respective end walls, and means operable while the electrode and wallsare non-contacting and while the terminals of the arcs are maintained inengagementwith saidelectrode and the respective end walls for moving theare along and throughout'the predetermined extended length, with,sufllclent rapidity and a sui'ilcient number of times to heat the endwalls substantially uniformly throughout the predetermined extendedlength. I

3. A machine bers each provided with a wall having. in combination,anelectrode, means for holding said electrode so that it is disposedadjacent the walls throughout a predetermined extended length but withthe electrode separated from each of the 'walls at all points of thepredetermined extended length by a'gap, means for impressing oppositepotentials between the electrode and the members to produce an arc ineach gap while the electrode is held separated from the walls, meansoperable whilethe electrode and walls are held separated irom'each otherfor moving the arcs in the gaps along and throughout the predeterminedextended length, with suflicient rapidity and a sufll cient number oftimes to heat the walls substantially uniformly throughout thepredetermined extended length, and means for pressing the membersrelatively toward each other to bring the heated walls into tightengagement, thereby tocause the members to become welded to each otheralong the heated walls.

4. A machine for welding together two memoperable while the walls areheld separated from 7 each other for establishing in each gap a magneticfield having .a substantial component at right angles to the lengthdimension of the'gap to cause the arc to travel in the gap along andthroughout the predetermined extended length,

with suillclent rapidity and a sufllcient number of times to heat thewalls substantially uniformfor striking an are between said for weldingtogether two mem each provided with a wall having, in combinav tion, anelectrode, means for holding said electrode so that it is disposedadjacent the walls throughout a predetermined extended length but withthe electrode'separater from each of the walls at all points of thepredetermined extended length by a gap, means for impressing opposite.potentials between the electrode and the members to produce an arc ineach gap while the'electrode is held separated from the walls, meansoperable while the electrode and walls are held separated from eachother for establishing in the gap a magnetic field having a substantialcomponent at right angles to the length dimension of the gap to causethe arc to travel in'the gap along and throughout the predeterminedextended length, with sufficient rapidity and a sufllcient number oftimes to heat the walls substantially throughout the predeterminedextended length.

6. A machine for heat-processing two members each provided with a wallhavin in combination, a refractory electrode, means for holding saidelectrode so that it is disposed adjacent each gap while the electrodeis held separated from the walls, means operable while the elec- 7. Amachine for heat-processing two members each provided with a wallhaving, in combination, a refractory carbon electrode, means for holdingsaid electrode so that it is disposed adjacent the walls throughout apredetermined extended length but. with the electrode separated fromeach of the walls at all points of the predetermined extended length bya gap,

means for impressing opposite potentials between the electrode and themembers to produce an arc trode and walls are held separated from eachthe walls throughout apredetermined extended length but with theelectrode separated from each of the walls at all points of thepredetermined extended length by a gap, means for impressing oppositepotentials between the electrode and the members to produce an arc ineach gap while-the electrode is held separated from the walls, meansoperable while the electrode and walls are held separated from eachother for establishing in the gap a magnetic field having a substantialcomponent at right angles to the length dimension of the gap to causethe arc to travel in the gap along and throughout the predeterminedextended length, with sufiicientrapidity and a sufilcient number oftimes to heat-the walls substantially throughout the predeterminedextended length.

other for establishing in the gap a magnetic field having a substantialcomponent at right angles to the length dimension of the gap to causethe arc to travel in the gap along and throughout the predeterminedextended length, with sufiicient rapidity and a sufiicient number oftimes to-heat the walls substantially throughout the predeterminedextended length.

8. A machine for heat-processing two members each provided with a wallhaving, in combination, an electrode, means for holding said electrodeso that, it is disposed adjacent the walls throughout a predeterminedextended length but with the electrode separated from each of the wallsat all points of the predetermined extended length by a gap, means forimpressing opposite potentials between the electrode and the members toproduce an arc in each gap while the electrode is held separated fromthe walls, means operable while the electrode and walls are heldseparated from each other for establishing in the gap a magnetic fieldhavinga substantial component at right angles to the length dimension ofthe gap to cause the arc to travel in the gap along and throughout thepredetermined extended length, with sufiicient rapidity and a suflicientnumber of times to heat the walls substantially throughout thepredetermined extended length, said electrode being movable into and outof arc-sus taining position with respect ,to said walls.

ELM'ER J. GORN.

